Escorts

The convoy system is about as old as sea trade
itself. Vessels would travel together for mutual support in pirate haunted
seas or in times of war.

The value of the convoy system to Britain which
relied on sea trade for survival was well learnt, during the wars with
France in particular the convoy system was well established and each
would normally be protected by RN Sloops and Frigates. So important
was the convoys that Nelson went into battle at Trafalgar without most
of his Sloops and Frigates as they were left in the Mediterranean to
guard vital convoys.

Demand for these small general purpose ships
was often torn between the need of the Fleet and the protection of convoys,
and this situation did not change when the Destroyer came along to replace
them.

A convoy gathers in WWII

Despite
the long practise of the convoy the Admiralty made no attempt to instigate
the system at the start of WW1, arguing that a convoy would simply represent
a large target for modern raiders.

In part this had merit, the speed difference
between a merchantman and a warship had become profound. Previously
an outgunned escort could be expected to delay an attacker while a convoy
scattered for safety, but now it was argued that a modern surface raider
would easily catch the fleeing ships one by one. A similar argument
was used against the U-Boat, that an attacking boat would simply flood
the convoy area with torpedoes to devastating effect.

It was the French who managed to get the convoy
system reinstated, to some degree. France relied heavily on imports
of British coal and these were being decimated by U-Boat attacks. Pressure
was brought to bear and the Admiralty reluctantly organised the collier
ships into convoys, with an immediate and measurable improvement in
survivability.

Limited convoys were introduced elsewhere and
proved their worth, with the advent of unrestricted submarine warfare
in 1917 losses rocketed and finaly Atlantic convoys were introduced
and were highly succesful.

But the Admiralty was very reluctant to release
Destroyers to the task of escort, preferring to keep them as Fleet Units.
Older Destroyers were released, but proved less than suitable, designed
for high speed operations they did not perform well at slow convoy speeds
and lacked adequate range.

SMS Scharnhorst, one of the German cruisers sent
to sea at the start of WW1 to raid British shipping around the world.
One argument against convoys was raiders like this would find them easy
pickings.
HMS Venomous, Destroyers were considered too valuable as Fleet Escorts
to be used as Convoy Escorts, and their design did not suit long slow
hauls defending a slow moving convoy.

Sloops
had been re-introduced during the war, these were cut down Destroyers,
slower and less well armed, they were designed to act as Fleet Minesweepers.
A number of these were released for convoy escort work and proved very
effective, later builds of Sloops omitted the mine sweeping gear in
favour of all depth charges and some were designed to resemble merchantmen
to lure U-Boats into a surface engagement. History knows these as Q-Ships.

After the war those Sloops kept in service were
assigned to roles as colonial gunboats, where they again showed their
worth and more were built to replace them. But in defiance of experience
these between the war Sloops were again built to have a wartime role
as Fleet Minesweepers rather than as Escort Vessels.

Concentrating on conventional gun armaments and
relatively high speeds the ships could only by constructed in specialist
military yards and with the outbreak of WWII Germany immediatley launched
a fierce submarine war against Britain, using their experience gained
from WWI. Although this time the convoy system was re-introduced at
once this time a severe lack of escorts and the U-Boat tactic of massing
into Wolf Packs before attacking meant that convoys began to suffer
heavy losses.

Unable to build Sloops in sufficient numbers
the RN rushed small merchant built Corvettes into service, then larger
Frigates built along similar lines. A dedicated Escort Destroyer, the
Hunt Class was introduced, but although it excelled in the hostile air
enviroments of the North Sea and Mediterranean they were - like their
WWI counterparts - unsuitable for the long slow slog of the Atlantic
convoys. Although America and Australia embraced the Escort Destroyer
(DDE) concept the RN firmly rid itself of it post war.

With the advent of new and faster submarines,
late in the war by the Germans and then adopted and improved on by Soviet
Russia post war, the RN believed only an Escort vessel as fast as the
new submarines would suffice to defend against them and modified war
time destroyers into fast frigates and general purpose Escorts, these
latter, although by every definition in fact Destroyer Escorts, were
nevertheless also classed as Frigates.

Although virtualy bankrupt there was a critical
post war need for a purpose built escort vessel which could be mass
produced at need as all war built Escorts were now perceived as obsolete.
Alliance, later formalised as NATO, strategy called for a rapid reinforcement
across the Atlantic in the event of war with Russia, the convoys would
have to be guarded and so would the carrier task forces which would
act as hunter killer groups. Although the converted Destroyers provided
a stop gap measure they suffered from the same problems Destroyers had
in the past: poor range, inefficient and unstable at low speeds, and
built for speed they lacked the hull capacity for new technology systems.

Designers then had a seemingly impossible task.
They needed a ship with the speed of a Destroyer, which could cruise
at low speed, operate in any weather, carry extra equipment and was
cheap and easy to build. The DDE concept was attractive since it seemed
to promise an all purpose ship, but having faced near defeat twice now
to the Submarine the RN was not to be seduced. In the Type 15 and Type
16 they had a comparison between a dedicated ASW ship and the DDE general
purpose and the value of the dedicated ship was soon proven in trials
and excercises.

HMAS Marguerite, classed as Fleet Minesweepers
the WW1 Flower Class Sloops saw extensive service as convoy escorts
later in the war once the convoy system was initiated. Typical of the
class she carried minimal guns, her Minesweeping gear could be replaced
by depth charges and they were able to cruise with a convoy for long
distances in all weathers.Despite the bitter lessons of WW1 the RN on the
eve of WWII was without a dedicated anti-submarine Escort Ship. The
Flower Class like HMS Betony pictured above were a desperate attempt
to remedy that.
HMS Oakley, the Hunt Class Destroyer was an attempt to produce a budget
Destroyer that could serve as a convoy escort. The relatively small
space given to depth charges compared to guns reflects the reluctance
to drastically alter traditional Destroyer armaments. Possibly one reason
why the Frigate Class was re-introduced, in order to make a clear distinction
between the role of Convoy and Fleet Escort.

As
in the previous two wars it was anticiapated the main battleground would
be the coasts of Britain, the approaches to the Atlantic and the Atlantic
itself. Escort ships would need to protect both the convoys and the
Carrier Task Groups that would form the core of hunter killer groups.
One hard won lesson was that a convoy was not just a good form of defence,
it was also bait, instead of hunting the oceans for illusive submarines
a Hunter Killer Group had only to intercept enemy submarines as they
sought to catch a convoy.

A number of different types of Escort were anticipated
would be needed, mirroring in many ways the ships that had served in
WWI and WWII, from small coastal escorts to long range deep ocean escorts
and from air defence ships when operating in reach of enemy aircraft
to fast submarine killers. Work began on the design of a hull which
could be common to as many of these requirements as possible, following
the example of the Loch Class which had proved adaptable to the Bay
Class anti-aircraft Frigate, a standerdised hull would cut costs immensely
and with pre-fabrication ensure the rapid build up of forces even if
specialist dockyards were destroyed

HMS Termagant, a T Class Destroyer converted to
an Escort Vessel. Armed with guns, torpedoes and Squid depth charge
mortars she was technicaly an Escort Destroyer (DDE) but the RN began
to classify any ship whose primary role was Escort as a Frigate, later
the term would term would change to mean a small Anti Submarine ship